1. Field of the Invention
This invention is directed to a unit for maritime use for the electrocatalytic treatment of wastewater containing suspended organic solids and pathogenic organisms.
2. Description of the Prior Art
The electrolytic treatment of sewage water mixtures to both disinfect sewage and remove a portion of the suspended solids therefrom is known. Reference is made, for example, to the following United States patents disclosing electrolytic treatment of sewage-water: U.S. Pat. Nos. 3,616,355; 3,756,933; 3,764,500; 3,766,033; 3,856,642; 3,925,176; 3,939,499; 3,943,044; 3,975,247; 3,975,256; 4,009,104; and 4,045,314. Reference is also made to U.S. application Ser. No. 882,264 filed Feb. 28, 1978 and now U.S. Pat. No. 4,179,347, which discloses an electrocatalytic treatment system wherein a measured quantity of an electrolyte, generally salt, is added to an influent wastewater stream and the wastewater stream is passed through a plurality of closely spaced planar electrocatalytically active electrodes where chlorine, oxygen and other disinfecting chemicals are generated in situ. Foam containing entrained suspended solids are removed from the cell and the treated wastewater stream is discharged from the treatment vessel into a filter for removal of fibrous residual suspended solids. The amount of residual chlorine present in the treated wastewater stream discharged from the electrocatalytic treatment vessel is controlled by measurement of the conductivity of the wastewater stream entering the electrolytic treatment vessel and control of the amount of electrolyte added to the incoming stream.
Water pollution control permits are increasingly being required for any type of vessel which moves on the water within the territorial limits, both in the United States and other countries. In the United States the Coast Guard is responsible for issuing of such permits. The standards required for discharge of effluent into maritime waters are becoming more and more severe in terms of suspended solids content, level of BOD and fecal coliform count. Vessels operating within the territorial waters either have to have holding tanks to receive all wastewater and hold it until it can be pumped to an on-shore treatment facility or the vessel will have to have a treatment facility on board capable of treating the wastewater such that the effluent discharged meets designated standards. The on-board treatment systems generally available today are expensive, hard to maintain, require chemical additives and are bulky. It has remained a problem to develop a compact, low weight, relatively small low-cost unit which may be used for new vessels or to retrofit existing vessels.